6/15 UWorld Flashcards
1
Q
What is the source and function of ANP and BNP
A
- Released from atrial (ANP) and ventricular (BNP) myocytes in response to increased blood volume
- Acts via cGMP
- Causes vasodilation and decreased Na+ reabsorption at the renal collecting tubule
- Dilates afferent arteriole and constricts efferent arterial, promoting diuresis
2
Q
Adverse effects of Digoxin
A
- Hyperkalemia (recall that dysfunctional Na+/K+ ATPase blocks K+ from entering the cell, so it builds up in the serum instead)
- Premature ventricular contractions and other arrhythmias
- Digitalis effect = T-wave changes, QT interval shortening, ST depression
- = taSTy scoop of ice cream = “scooped”/concave ST depression of EKG
- Bradycardia due to parasympathetic activity at SA node
- à SA music “note” (node) on top L of dancefloor
- à dangling heart watch = bradycardia
- Heart block due to excess parasympathetic activity of AV node in digoxin toxicity
- à AV music note
- à heart shield pendant on girl = heart block
- Contraindicated in heart block (or other drugs that depress SA or AV nodes e.g. beta-blockers)
- à sign over door: “remain unblocked”
- à blocked is spelled with a ‘beta’ B
- GI symptoms (nausea, vomiting, abd pain)
- à nauseated kid
- Neuro sx (confusion and weakness)
- Alteration in color vision
- Xanthopsia (objects appear yellow)
3
Q
Factors that exacerbate Digitalis toxicity
A
- Hypokalemia (hypokalemia increases Digoxin binding to Na+/K+ ATPase)
- Can be caused by loop diuretics or diarrhea
- Renal insufficiency
- Increased the serum half life of digoxin, increasing susceptibility to toxicity
- Many antiarrhythmics inhibit renal clearance of digoxin, increasing susceptibility to toxicity
4
Q
MOA of Milrinone
A
- Sketchy = “One in a million” sign
- Phosphodiesterase inhibitor, leading to decreased breakdown of cAMP, leading to a positive inotropic effect
- = “Don’t phoster disinterest” sign
- = CAMPaign
- = big muscles of donkey = positive inotropic effect
- Also causes arteriolar dilation and decreased afterload
5
Q
MOA of Nesiritide
A
- Sketchy = “Turn the tide” elephant
- Synthetic form of BNP, which increased cGMP in smooth muscles, leading to venous and arteriolar dilation (reducing afterload and preload)
- = BuMP
- = dilated red ears and blue legs
- Also causes natriuresis
6
Q
Describe the effects of prostaglandins and ATII on GFR
A
Prostaglandins dilate the afferent arteriole = increased GFR
ATII constricts the efferent arteriole = increased GFR
Coadministration of NSAIDs and ACEi will lead to significantly decreased GFR due to contricted afferent and dilated efferent arteriole - can precipitate kidney injury
7
Q
MOA of Aliskiren
A
- Sketchy = “High risk” slots
- Mechanism of action
- Direct Renin inhibitor
- Prevents conversion of angiotensinogen to ATI
8
Q
What drugs improve mortality in chronic CHF patients vs. drugs that treat symptoms?
A
- Improved survival:
- ACEI
- ARBs
- Aldosterone antagonists
- B-blockers
- Symptomatic relief:
- Diuretics
- Digoxin
- Vasodilators
9
Q
Cause, CO, SVR, and Rx of Septic/Anaphylactic shock
A
- Sepsis/anaphylaxis
- Sepsis and anaphylaxis cause vasodilation and leaky capillaries
- Skin will be warm and flushed to do vasodilation
- SVR = Decreased (this is part of the cause of septic shock)
- CO = Increased (compensatory tachycardia)
- Rx = Antibiotics, IV fluids, vasopressors (norepinephrine)
- Sepsis and anaphylaxis cause vasodilation and leaky capillaries
10
Q
Cause, CO, SVR, and Rx of Neurogenic shock
A
Brain is not communicating properly with the heart – e.g. brain injury, spinal cord injury
CO = Decreased
SVR = Decreased
Rx = IV fluids
11
Q
On a pressure-volume loop of the LV, describe where on the graph the mitral valve and aortic valve close and open
Volume on the X-axis and pressure on the Y-axis
A
12
Q
Adverse effects of Milrinone
A
Hypotension
Due to arteriolar dilation
13
Q
In the cardiac cycle graph, show were mitral and aortic valve opening and closing occur
A
14
Q
Label the jugular venous tracing graph
A
A wave = atrial contraction
C wave = ventricular contraction
V wave = atrial filling against closed tricuspid valve
15
Q
Describe what normal heart sound splitting is
A
Inspiration = decreased intrathoracic pressure = increased venous return = increased RV filling = increased RV stroke volume = increased RV ejections time = delayed closure of pulmonic valve
16
Q
When do you see wide splitting vs. fixed splitting
A
- Wide splitting:
- Splitting occurs both in inspiration and expiration
- Due to conditions that delay RV emptying (e.g. Pulmonic stenosis, R bundle branch block)
- Fixed splitting:
- Occurs during right heart overload (e.g. atrial septal defect)
- ASD –> L-to-R shunt –> increased RA and RV volumes –> increased flow through pulmonic valve such that, regardless of breath, pulmonic closure is delayed
17
Q
Describe paradoxical splitting
A
- Due to conditions that delay aortic valve closure (e.g aortic stenosis, left bundle branch block)
- Normal order of valve closure is reversed so that P2 occurs before delayed A2
- On inspiration, P2 closes later and moves closer to A2, thereby “paradoxically” eliminated the split
18
Q
What maneuver enhances mitral regurg vs. tricuspid regurg
A
Mitral regurg enhanced by increased afterload (e.g. hand grop or squatting)
Tricuspid regurg enhanced by increased preload (e.g. inspiration)
19
Q
Causes of aortic regurgitation
A
Aortic root dilation (e.g. syphilis or Marfan)
Bicuspid aortic valve
Endocarditis
Rheumatic fever
20
Q
What murmurs are increased by inspiration vs. hand grip vs. valsalva
A
- Inspiration:
- This decreases intrathoracic pressure, thus increased venous return to the heart
- Increased intensity of R heart sounds (e.g. Tricuspid murmur)
- Hand grip:
- This increases SVR, this increasing afterload
- Increased intensity of mitral regurgitation, aortic regurgitation, and VSD
- Valsalva maneuver
- This increases intrathoracic pressure, thus decreasing preload (opposite of inspiration)
- Decreases the intensity of most murmurs EXCEPT increases intensity of hypertrophic cardiomyopathy
21
Q
Complications/presentation of aortic stenosis
A
SAD:
Syncope, angina, dyspnea
22
Q
Describe electrolytes responsible for each phase in cardiac myocyte fast action potential (Phase 4, 0, 1, 2, 3)
A
- Stage 4 (baseline negative state)
- Only “leaky” potassium channels open (K+ leaking out of cell - inward rectifier current)
- Stage 0
- Voltage gated Na+ channels open (after threshold -70 is reached by Na+ and Ca+ leaking through gap junctions)
- Na enters very quickly à fast depolarization
- Stage 1
- Initial repolarization – Na+ channels close and voltage gated K+ channels open (K+ leaves cell), causing repolarization
- Stage 2
- Plateau – Ca2+ channels open (Ca enters cells) – L-type channels
- Ca2+ and K+ channels pull voltage in opposite directions, so reach sort of plateau
- This is the phase that causes myocyte contraction (due to Ca2+ triggering more Ca2+ release from sarcoplasmic reticulum)
- Stage 3
- Rapid repolarization – Ca2+ channels close, so only K+ channels open
- But eventually the voltage gated K+ channels will close, leaving only open the “leaky” potassium channels, so there is membrane stabilization
23
Q
Describe electrolytes responsible for each phase of pacemaker slow action potential
A
- Stage 4
- Na+ channels (If – funny current) are open (Na+ enters cells) and allow depolarization (voltage gated K+ channels are closed)
- The rate of stage 4 depolarization is what sets the heart rate
- Stage 0
- Threshold reached where voltage gated Ca2+ channels open causing more rapid depolarization at threshold (-40)
- Ca2+ enters pretty quickly, but not as quickly as Na+ in stage 0 of myocytes à slow action potential
- Stage 3
- At threshold +10, voltage gated Ca2+ channels close and voltage gated K+ channels open (potassium leaves cell), causing repolarization (at -60, the voltage-gated K+ channels will close and Na+ channels will reopen)
- At certain threshold, K+ channels close, so Na+ is only channel open and cycle restarts
24
Q
What is Addison disease
A
Autoimmune destruction of the adrenal gland
Decreased aldosterone and cortisol
25
What is Conn syndrome
Primary hyperaldosteronism due to adrenal adenoma
26
What disease is associated with nephritis, hearing loss, and cataracts
Alport syndrome - defect in collagen type IV
"Cant see, cant pee, cant hear high C"
27
Immunochemistry staining that can differentiate complete mole from partial mole
* Complete mole will be p57 negative (p57 protein is a product of paternally imprinted by maternally expressed gene)
* Can use this to differentiate from a partial mole which will be p57 positive
28
Tumor marker of choriocarcinoma
b-hCG
29
What does tumor marker CEA indicate
§ Colon cancer
§ Pancreatic cancer
30
What does tumor marker CA 19-9 indicate
§ Pancreatic cancer
31
What form of Vitamin D is calcitriol, and what is it stimulated by
Active form fo VD (1, 25-dihydroxyvitamin D)
Stimulated by PTH, which increases the enzyme in the kidney that does the final step of VD activation
32
What does an elevated alk phos level suggest?
Hepatobiliary disease
Bone problems
33
In the setting of elevated alk phos, what other lab value can indicate if cause is hepatobiliary or bone?
gamma-glutamyl transpeptidase (GGTP)
Found predominanlty in hepatocytes and biliary epithelium, so if elevated, suggests hepatic origin over bone origin
34
What is the timeframe difference between mania and hypomania
* Mania = last at least 1 week
* Hypomania = last at least 4 consecutive days
* Not severe enough to cause marked impairment in social or occupational function
35
Differentiate Bipolar I vs. Bipolar II vs. Cyclothymic disorder
* Bipolar I
* 1 manic episode +/- a hypomanic or depressive episode
* Depression not necessary for diagnosis
* Bipolar II
* Hypomanic episode + major depressive episode
* Cyclothymic Disorder (milder)
* Mild hypomanic symptoms + mild depressive symptoms
* Lasts \> 2 years
36
What part of tRNA do amino acids bind to during "loading"
3' terminal hydroxyl group of the CCA tail on the acceptor stem
Aminoacyl tRNA synthetase is responsible for "loading"
37
Diagnostic criteria for Tourretes
* Both multiple motor and \>/= 1 vocal tic for \> 1 year
* Motor = facial grimacing, blinking, head/neck jerking, shoulder shrugging, tongue protrusion, sniffing
* Vocal = grunts, snorts, throat clearing, barking, yelling, coprolalia (obscenities)
38
Diagnostic criteria for Chronic tic disorder
* Either motor or verbal tics (but not both) for \> 1 year
39
Differentiate delusional disorder from schizophrenia
* Diagnosis of schizophrenia – requires at least 2 of the following, with at least one from 1-3:
* Delusions
* Hallucinations
* Disorganized speech
* Disorganized or catatonic behavior
* Negative symptoms (affective flattening, avolition, anhedonia, asociality, alogia)
* Delusional disorder:
* \>/= 1 delusions for \>/= 1 month
* Other psychotic symptoms absent or not prominent
* Ability to function apart from delusion; behavior not obviously bizarre or odd
40
What is schizofreniform disorder vs. shizoaffective disorder
* Schizophreniform disorder
* Schizo sx \> 1 month and \< 6 months
* \> 6 months becomes schizophrenia
* Schizoaffective disorder:
* Mood episodes and active symptoms of schizophrenia occurring at the same time + at least 2 week lifetime history of delusions or hallucinations in the absence of prominent mood symptoms
* Aka normal schizo sometimes and schizo + mood at other times
41
What is brief psychotic disorder
Schizo sx \> 1 day and \< 1 month
\> 1 month = schizophreniform disorder
\> 6 months = schizophrenia
42
What is the target vessel in a central line
SVC
Usually inserted into internal jugual vein
43
What is the stool microscopy test used to identify unabsorbed fat in stool
Sudan III stain
44
What type of patients are at a higher risk for developing drug-induced lupus
Slow acetylators
Higher levels of drugs that cause DILE
45
What antibody is indicative of drug-induced lupus
anti-histone
46
MOA of Bosentan
* Sketchy = Boss man stan
* Block endothelin (which usually is a potent vasoconstrictor) leading to vasodilation and decreased pulmonary pressure
* Used to treat pulmonary HTN
47
What is the reasoning behind adding Primaquine on top of Chloroquine for malarial treatment
Chlorquine eradicates chloroquine-sensitive plasmodia from the bloodstream, but has no activity against latent hepatic infection established by P vivax and P ovale
Primaquine must be added to eradicate hypnozoites
Skethchy = Primal queen needed when Color Queen is hypnotized by Vivax and Ovale
48
What is the reason behind starting patients on ASA when they are at risk for cardiac events
Inhibition of COX-1 in platelets prevents synthesis of TXA2, a stimulator of platelet aggregation and vasoconstriction
49
Label the nerves exiting the brainstem
50
Most common causes of bacterial meningitis in neonates and adults
* Neonates:
* Group B strep
* Gram negative bacilli (E. coli)
* Listeria
* Adults:
* Strep pneumoniae
* Neisseria meningitides
* H. flu type B
51
What are the layers of the epidermis
* Stratum corneum lucidum, granulosum, spinosum, basale
* THINK: Californians Like Girls in String Bikinis
52
Describe histology of psoriasis
* Acanthosis (epidermal hyperplasia)
* Increase in stratum spinosum and decrease in stratum granulosum
* Parakeratosis (hyperkeratosis with retention of keratinocyte nuclei in the stratum corneum)
* Munro microabscesses (neutrophils within the stratum corneum)
* Auspitz sign (pinpoint bleeding due to thinning of epidermis above elongated dermal papilla)
53
What is an ecological study
Looks for associations between a given characteristic and a given outcome using **_population data_**
Can be used to generate hypothesis by should not be used to make conclusions about individuals within these populations
54
What type of colon cancer has "cauliflower-like" appearance
Villous adenoma
